AuxXxilium/linux_dsm_epyc7002
1
0
Fork 0
mirror of https://github.com/AuxXxilium/linux_dsm_epyc7002.git synced 2024-12-28 11:18:45 +07:00
Code Issues Actions Packages Projects Releases Wiki Activity

arm64: bti: Fix support for userspace only BTI

Browse Source 
When setting PTE_MAYBE_GP we check system_supports_bti() but this is
true for systems where only CONFIG_BTI is set causing us to enable BTI
on some kernel text. Add an extra check for the kernel mode option,
using an ifdef due to line length.

Fixes: c8027285e3 ("arm64: Set GP bit in kernel page tables to enable BTI for the kernel")
Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20200512113950.29996-1-broonie@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
This commit is contained in:
Mark Brown 2020-05-12 12:39:50 +01:00 committed by Will Deacon
parent 3a88d7c5c9
commit e4e9f6dfee
1 changed files with 8 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

8
arch/arm64/include/asm/pgtable-prot.h
View File

@ -32,7 +32,15 @@ extern bool arm64_use_ng_mappings;
#define PTE_MAYBE_NG (arm64_use_ng_mappings ? PTE_NG : 0)
#define PMD_MAYBE_NG (arm64_use_ng_mappings ? PMD_SECT_NG : 0)
/*
* If we have userspace only BTI we don't want to mark kernel pages
* guarded even if the system does support BTI.
*/
#ifdef CONFIG_ARM64_BTI_KERNEL
#define PTE_MAYBE_GP (system_supports_bti() ? PTE_GP : 0)
#else
#define PTE_MAYBE_GP 0
#endif
#define PROT_DEFAULT (_PROT_DEFAULT | PTE_MAYBE_NG)
#define PROT_SECT_DEFAULT (_PROT_SECT_DEFAULT | PMD_MAYBE_NG)